Due to a buffer overflow vulnerability in the SRX Series flow daemon (flowd) while processing certain crafted telnet protocol messages, a remote attacker may be able to execute arbitrary code leading to a complete compromise of the system. This issue only occurs if telnet pass-through authentication is configured on the firewall. A sample affected configuration is shown below:

Customers can confirm the build date of any Junos OS release by issuing the command 'show version detail'.

This issue is being tracked as PR 861558 and is visible on the Customer Support website.

KB16765 - "In which releases are vulnerabilities fixed?" describes which release vulnerabilities are fixed as per our End of Engineering and End of Life support policies.

Workaround:

If telnet pass-through authentication is not required, disabling the feature will completely mitigate this vulnerability.

Implementation:

How to obtain fixed software:

Security vulnerabilities in Junos are fixed in the next available Maintenance Release of each supported Junos version. In some cases, a Maintenance Release is not planned to be available in an appropriate time-frame. For these cases, Service Releases are made available in order to be more timely. Security Advisory and Security Notices will indicate which Maintenance and Service Releases contain fixes for the issues described. Upon request to JTAC, customers will be provided download instructions for a Service Release. Although Juniper does not provide formal Release Note documentation for a Service Release, a list of "PRs fixed" can be provided on request.